A woman drinking a cup of coffee

Coffee carries life-lengthening health benefits, but not if you're adding flavors and creams to it. (Photo by Cast Of Thousands on Shutterstock)

In a nutshell

  • Coffee drinkers who consumed 1-3 cups daily had a 15-17% lower risk of dying early compared to non-coffee drinkers
  • Health benefits only applied to black coffee or coffee with minimal added sugar (less than half a teaspoon per cup) and saturated fat
  • Coffee drinks high in sugar and saturated fat showed no protective effects, potentially eliminating coffee’s health benefits entirely

MEDFORD, Mass. — Americans love their coffee, with about half of us reaching for a cup every single day. And here’s some news that might make your morning brew taste even better: that daily coffee habit could be cutting your risk of dying early by up to 17% — but there’s a catch that could cancel out the benefits.

A study tracking nearly 50,000 American adults for more than a decade found that coffee drinkers lived longer than those who skipped their daily caffeine fix. The twist? The life-extending benefits were only seen in people who drank black coffee or coffee with very little added sugar and saturated fat. Those sugary, creamy coffee shop drinks? They offered no measurable health advantage.

According to the study, coffee with higher levels of added sugar and saturated fat was not associated with lower death rates. Moreover, the benefits were not seen in people who preferred a decaf brew. The research took a detailed look at what Americans are actually putting in their coffee, and the findings raise red flags about our sweetened coffee culture.

Nearly 50,000 Americans Tracked for Over a Decade

Researchers from Tufts University analyzed coffee drinking habits and health outcomes in 46,322 adults aged 20 and older who participated in U.S. government health surveys between 1999 and 2018. Participants were followed for roughly 9 to 11 years, with actual mortality outcomes tracked using National Death Index records.

During that time, 7,074 participants died — 1,176 from cancer and 1,089 from cardiovascular disease. Compared to non-coffee drinkers, those who drank coffee had significantly lower mortality rates. The greatest benefit appeared in people drinking 2 to 3 cups a day, who had a 17% lower risk of dying during the follow-up period. Even those who drank less than a cup a day saw an 11% lower risk.

person holding white cup pouring coffee
Taking your coffee black is best if you’re hoping to enjoy its health benefits. (Photo by John Schnobrich On Unsplash)

Why Sweetened Coffee May Cancel the Health Benefits

The researchers also examined what went into those cups of coffee. Each beverage was classified based on how much added sugar and saturated fat it contained per 8-ounce serving.

Drinking black coffee was associated with a 14% lower risk of all-cause mortality. Coffee with small amounts of added sugar (under 2.5 grams per cup) and saturated fat (under 1 gram per cup) also showed the same 14% reduction.

But for people drinking coffee with higher amounts of sugar and saturated fat, there was no statistically significant reduction in risk of death. For context, the average U.S. coffee drink contains 3.24 grams of added sugar and 0.52 grams of saturated fat per 8-ounce cup, suggesting that many Americans are overshooting the threshold where coffee may offer health benefits.

Caffeine Key to Longevity

The study, published in The Journal of Nutrition, also found that caffeinated coffee — not decaf — was driving most of the observed health benefits. While decaffeinated coffee showed no clear association with longevity, caffeinated coffee was linked to reduced risk of death from both all causes and cardiovascular disease.

That’s in line with previous research suggesting that caffeine may play a protective role by boosting metabolism, reducing inflammation, and improving insulin sensitivity. Coffee also contains other bioactive compounds like chlorogenic acid and polyphenols that are thought to have antioxidant and anti-inflammatory effects.

Interestingly, the protective effects of coffee were only observed among people who did not drink tea. Among tea drinkers, the association between coffee and longevity disappeared, though the study doesn’t explain why.

ice cream in clear glass cup
The study isn’t good news for those who enjoy fancy orders at their favorite coffee shop. (Photo by Tabitha Turner at Unplash)

It’s Best To Be Basic

For the estimated 150 million Americans who drink coffee daily, this study delivers both a bit of good news and a wake-up call. The good news: your coffee habit could be helping you live longer. The reality check: if your go-to drink includes lots of sugar, cream, or flavored syrups, those potential benefits may be lost.

Researchers adjusted for a wide range of lifestyle and health variables, including age, sex, race, income, smoking, alcohol use, exercise, diet quality, and preexisting conditions. Even then, the association between simple coffee and lower mortality still held up.

The takeaway? A basic cup of coffee, especially when consumed black or lightly sweetened, may be one of the healthiest parts of your day. But when that cup starts to resemble dessert and doesn’t have caffeine, the health perks may disappear.


Paper Summary

Methodology

Researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2018, focusing on 46,322 adults aged 20 and older. They tracked coffee consumption using detailed 24-hour dietary recalls and categorized coffee types based on caffeine content and amounts of added sugar and saturated fat. Participants were followed for a median of 9.3 to 11.3 years, with mortality data obtained through linkage to the National Death Index through December 2019.

Results

During the follow-up period, 7,074 deaths occurred. Coffee consumption of 1-3 cups per day was associated with 15-17% lower all-cause mortality risk. The greatest benefit was seen with 2-3 cups daily (17% reduction). However, mortality benefits were limited to black coffee and coffee with low added sugar (<2.5g per cup) and low saturated fat (<1g per cup). Coffee with high levels of sugar and saturated fat showed no protective effects. The benefits were primarily associated with caffeinated rather than decaffeinated coffee. For cardiovascular disease mortality analysis, only data from 1999-2014 cycles were used.

Limitations

The study relied on one or two days of dietary recalls, which may not capture typical long-term intake patterns. Coffee consumption correlates with various lifestyle factors, and while researchers adjusted for known confounders, residual confounding cannot be ruled out. The study couldn’t distinguish between different types of cancer deaths due to small numbers, and information about coffee preparation methods wasn’t available.

Funding and Disclosures

This study was supported by the National Institutes of Health (award number R01MD011501). One author (FFZ) reported financial support from NIH, while all other authors reported no conflicts of interest. The funding sources had no role in study design, data collection, analysis, or manuscript preparation.

Publication Information

“Coffee Consumption and Mortality among United States Adults: A Prospective Cohort Study” by Bingjie Zhou, Mengyuan Ruan, Yongyi Pan, Lu Wang, and Fang Fang Zhang, published in The Journal of Nutrition, 2025. The study was received December 6, 2024, revised April 29, 2025, and accepted May 7, 2025.

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3 Comments

  1. Chesterton Haskerville says:

    Tea is better in every way over coffee imo. Coffee tastes like you took a dirty sock & filtered mud puddle water through it.

  2. Robert Hunter says:

    Black coffee is “coffee”. Everything else is a coffee “drink”.

  3. Brad M says:

    Decaf coffee actually has caffeine. A grande decaf at Starbucks advertises 25mg. That’s nearly as much as a soda.